JVC RX-6032VSL Service Manual page 19

4.11 LA1838 (IC102): FM AM IF Amp. & Detector, FM MPX decoder
• Block Diagram
30 29
AM
ALC
OSC
BUFF
SD
COMP
FM
S-CLRVE
S-METER
PM
FM IF
DET
1 2
• Pin Function
Pin No. Symbol
1 FM IN
2 AM MIX
3 FM IF
4 AM IF
5 GND
6
TUNED
7
STEREO
8 VCC
9 FM DET
10 AM SD
11 FM VSM
12 AM VSM
13 MUTE
14
FM/AM
15
MONO/ST
16 L OUT
17 R OUT
18 L IN
19 R IN
20 RO
21 LO
22 MPX IN
23 FM OUT
24 AM DET
25 AM AGC
26 AFC
27 AM RF
28 REG
29 AM OSC
30 OSC BUFFER
28 27 26 25
REG
AM FM
MIX RF.AMP
AGC
DET
AM IF
AM
S-METER
AM/FM
IF-BUFF
TUNING
DRIVE
GND
5
3 4 6
I/O
I This is an input terminal of FM IF signal.
O This is an out put terminal for AM mixer.
I Bypass of FM IF
I Input of AM IF Signal.
- This is the device ground terminal.
O When the set is tunning, this terminal becomes "L".
O Stereo indicator output. Stereo "L", Mono: "H"
- This is the power supply terminal.
- FM detect transformer.
- This is a terminal of AM ceramic filter.
O Adjust FM SD sensitivity.
O Adjust AM SD sensitivity.
I/O When the signal of IF REQ of IC121(LC72131) appear, the signal of FM/AM IF output.
//Muting control input.
I Change over the FM/AM input. "H" :FM, "L" : AM
O Stereo : "H", Mono: "L"
O Left channel signal output.
O Right channel signal output.
I Input terminal of the Left channel post AMP.
I Input terminal of the Right channel post AMP.
O Mpx Right channel signal output.
O Mpx Left channel signal output.
I Mpx input terminal
O FM detection output.
O AM detection output.
I This is an AGC voltage input terminal for AM
- This is an output terminal of voltage for FM-AFC.
I AM RF signal input.
O Register value between pin 26 and pin28 besides the frequency width of the input signal.
- This is a terminal of AM Local oscillation circuit.
O AM Local oscillation Signal output.
22 21
24 23
DECODER
ANIT-BIRDIE
STEREO
P-DET
VCO
384KHz
STEREO
DRIVE
VCC
8 9
7 10
Function
20 19 18
17
MUTE
5N
SW
FF
FF FF PILOT
/
38k 19k DET
19k LS
2 /
11 12 13 14
RX-6032VSL
16
15
(No.22012)1-19